In recent years, for example, portable media players, smart phones, and tablet terminals have become widespread as mobile terminals capable of downloading a large amount of data (for example, music, images, and Operating Systems (OSs)) while being connected to, for example, personal computers (PCs). These mobile terminals are configured to use the minimum necessary connectors in order to realize a stylish design.
Here, the shape of a connector used for connecting a cable used for charging and communication of a large amount of data (for example, an OS update) between the PC and the mobile terminal is relatively greater with respect to the shape of the mobile terminal. If the connecter can be omitted, a mobile terminal with a more stylish design can be expected.
Further, it is possible to omit the connector for connection between the mobile terminal and the PC, by using non-contact charging instead of charging using a cable, with respect to the charging. For example, many devices using the Qi standard of wireless power supply developed by the Wireless Power Consortium (WPC) have been commercialized.
Meanwhile, wireless communication using a 60 GHz band is used with respect to communication of a large amount of data, and thus communication of data over 1 Giga bit per second (Gbps) is possible. The communication standard of the 60 GHz band is developed by The Institute of Electrical and Electronics Engineers, Inc. (IEEE) 802.11ad, and commercialization is promoted by the Wireless Gigabit (WiGig) alliance.
IEEE 802.11ad assumes peer-to-peer communication in a short distance within several meters (m). Therefore, in the IEEE 802.11ad, a decrease in reliability occurring in a wireless Local Area Network (LAN), for example, a decrease in a transmission rate caused by connection of a plurality of mobile terminals or communication interference caused by a mobile terminal using another communication standard, is unlikely to occur, and reliability is high for communication of a large amount of data.
FIG. 16 is a diagram illustrating an example of a configuration of non-contact charging in the related art using a mobile terminal 101 and, for example, a terminal of a touch pad shape (hereinafter, referred to as a “pad terminal”). The pad terminal 102 is connected to a PC 103 or a backhaul through a cable. In FIG. 16, after the mobile terminal 101 is placed on a surface of the pad terminal 102, power is transmitted from a charging circuit 1125 (see a hatched part illustrated in FIG. 16) in the pad terminal 102 to a charging circuit 1115 (see a hatched part illustrated in FIG. 16) in the mobile terminal 101, and the mobile terminal 101 is charged in a non-contact manner.
FIG. 17 is a diagram illustrating an example of a configuration of non-contact charging in the related art using mobile terminals 50A, 50B, and 50C and a charging stand 20 (for example, see Patent Literature 1). After the plurality of mobile terminals 50A, 50B, and 50C are placed on a top plate 21, the charging stand detects the positions of the respective mobile terminals 50A, 50B, and 50C and moves respective power transmission coils 11 provided in the charging stand 20 along the top plate 21 by using a movement mechanism, not illustrated. The charging stand 20 moves the respective power transmission coils 11 close to power reception coils 51 of the respective mobile terminals 50, and performs non-contact charging after completion of an alignment between the respective power transmission coils 11 and the respective power reception coils 51.
FIG. 18 is a diagram illustrating an example of a configuration of non-contact charging in the related art using a pinless power jack 1100 and a pinless power plug 1200 (for example, see Patent Literature 2). The pinless power jack 1100 includes a primary induction coil 1120 coupled to a power source 1020 through a driving unit 1040, and a light receiver 3200. The pinless power plug 1200 includes a secondary induction coil 1220 coupled to an electric load 1400a, and a light transmitter 3100. The light transmitter 3100 and the light receiver 3200 are aligned on a central axis of the primary induction coil 1120, and data is transmitted and received by optical communication between the light transmitter 3100 and the light receiver 3200 through a shielding layer 1320. Further, power is transmitted and received by electromagnetic induction between the primary induction coil 1120 and the secondary induction coil 1220.
FIG. 19 is a front view of a spatial light transmission apparatus using light transmission in the related art (for example, see Patent Literature 3). The spatial light transmission apparatus includes a plurality of light projecting units 2 each in which a light projecting element is arranged behind a light projecting lens, and a plurality of light receiving units 3 each in which a light receiving element is arranged behind a light receiving lens. In the spatial light transmission apparatus, the light projecting units 2 and the light receiving units 3 are arranged while being distributed equally and alternately in vertical and horizontal directions on a plane, and thus a plurality of projecting light beams may be obtained as one thick light beam. Therefore, the spatial light transmission apparatus applies lights to the front of the spatial light transmission apparatus on the other side which is oppositely arranged, and thus it is possible to easily adjust the optical axes between both the spatial light transmission apparatuses.